Light emitting diode (LED) is a kind of optoelectronic semiconductor component which can convert current into light having a specific wavelength range. The light emitting diode is widely used as a light source for its high brightness, low voltage, low power consumption, easy matching with integrated circuits, simple drive, long life and other advantages. In order to make better use of light-emitting diodes, the light emitting diode is usually coated with a surrounding lens for secondary optical correction after encapsulation.
Light from the LED emits externally from top and side surfaces of the lens.